Progress 07/01/01 to 06/30/04
Outputs
We identified the sex pheromone of the obscure mealybug Pseudococcus viburni, in 2003, from a few micrograms of material in collected from mealybug colonies over many months. The active compound has a number of isomers, and all were made to conclusively verify the identity of the insect-produced compound. An efficient synthesis of the active compound, capable of being scaled up to produce multigram quantities, was then developed. The pheromone was field tested in California vineyards and nurseries, and by collaborators in South America and New Zealand. The pheromone is extraordinarily active, with lures loaded with submilligram quantities remaining attractive to male mealybugs for several months. Our first attempt to completely identify the pheromone of the longtailed mealybug failed due to the degradation of the isolated material during isolation and analysis. Two further consolidated batches of pheromone are in the final step of purification, and will be submitted
for NMR analysis in February. A manuscript describing the identification of the obscure mealybug pheromone is in preparation, and an American Chemical Society Symposium Series proceedings article on mealybug pheromones has been submitted and accepted.
Impacts
The output from this project to date has been the identification of the pheromones of two of the major mealybug pests of grapes in California, and many other grape-growing areas worldwide. Outcomes include providing pheromone trap technology for sampling vine mealybug and obscure mealybug, with longtailed mealybug pheromone in progress. The project has had a major impact in California. Thousands of vine mealybug pheromone traps have been used in statewide surveys to delineate the range of this introduced pest, and to detect low level infestations so that they can be eradicated. Experiments testing the use of the pheromone for control of vine mealybug through disruption of mating are in progress, by at least two companies. Furthermore, this pheromone has been rapidly picked up for use in other areas of the world, including South America, South Africa, and the Mediterranean basin. Because obscure and longtailed mealybugs are also widely distributed and polyphagous pests,
we fully anticipate that their pheromones also will find immediate use in insect monitoring and control programs.
Publications
- Daane, K.M., Bentley, W.J., Walton, V.M., Malakar-Kuenen, R., Millar, J.G., Gispert, C., Ingels, C.A., and Weber, E.A. 2004. Sustainable controls sought for vine mealybug. Cal Agricul. Submitted July 27/04. 32 ms pages.
- J.G. Millar, K.M. Daane, J.S. McElfresh, J.A. Moreira, and W.J. Bentley. 2004. Chemistry and applications of mealybug sex pheromones. ACS Symposium Series Volume, Semiochemicals in Pest Management and Alternative Agriculture; 20 camera-ready pp.; accepted June 18-04.
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Progress 01/01/03 to 12/31/03
Outputs
The sex pheromone of the obscure mealybug Pseudococcus viburni, has been isolated and completely identified from a few micrograms of material collected from mealybug colonies over many months. The active compound has been synthesized in milligram quantities to verify the structure, and the synthesized compound was highly attractive to male mealybugs in a preliminary field test. We are currently developing a more efficient, more stereoselective, and larger scale synthesis to provide multigram quantities for full-scale field tests to optimize operational details, such as dose, trap type, and field longevity of lures. Because the pheromone is so active, the amount synthesized should also provide enough material to initiate surveys for this pest in the areas throughout California where it is a pest. Our first attempt to completely identify the pheromone of the longtailed mealybug failed due to the degradation of the isolated material during isolation and analysis. Thus,
we are repeating the months-long aerations required to collect enough sample to attempt another NMR analysis. A manuscript describing the identification of the obscure mealybug pheromone is in preparation, and a further American Chemical Society Symposium Series proceedings article on mealybug pheromones has been submitted.
Impacts
The output from this project to date has been the identification of the pheromones of two of the major mealybug pests of grapes in California, and many other grape-growing areas worldwide. Outcomes include providing pheromone trap technology for vine mealybug, and by the end of the 2004 field season, obscure mealybug and possibly longtailed mealybug. The project has had a major impact in California. Thousands of vine mealybug pheromone traps have been used in statewide surveys to delineate the range of this introduced pest, and to detect low level infestations so that they can be eradicated. Experiments testing the use of the pheromone for control of vine mealybug through disruption of mating are also in progresss. Furthermore, this pheromone has been rapidly picked up for use in other areas of the world, including South America, South Africa, and the Mediterranean basin. It is being developed by at least 4 pheromone companies worldwide that we know of. Because
obscure mealybug is also a widely distributed pest, we fully anticipate that its pheromone also will find immediate use in insect monitoring and control programs when we finish its development in 2004.
Publications
- No publications reported this period
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Progress 01/01/02 to 12/31/02
Outputs
The sex pheromone of the vine mealybug Planococcus ficus has been developed for use in traps for sampling mealybug populations. All operational details, such as dose, trap type, field longevity of lures, etc. have been worked out, and pheromone-baited traps were used in a statewide survey for this pest in California during the 2002 growing season, carried out under the direction of project collaborators Kent Daane and Walt Bentley. In particular, the pheromone baited traps were able to detect low-level infestations of vine mealybug that had escapted detection by manual sampling methods at numerous locations. Many of these infestations are relatively small and isolated, and project collaborators are developing methods of eradicating these small scale and localized infestations before they spread further. Furthermore, a preliminary trial using a sprayable pheromone formulation for mating disruption of vine mealybug gave promising results, with trials to be greatly
expanded in the 2003 growing season. Identification of the sex pheromones for grape, obscure, and longtailed mealybugs are underway, with laboratory colonies of all three species established. One of these pheromones have now been tentatively identified and awaits synthesis, and both of the other pheromones now have been partially identified. For the latter two pheromones, pheromone collections are being made to provide sufficient material for completing the identifications.
Impacts
Since its introduction into California less than 10 years ago, the vine mealybug has rapidly become one of the most important vineyard pests in table, wine and raisin grapes. The sex pheromone baited traps developed in our research group have provided a simple and highly sensitive method for detecting new populations of this insect as it continues to spread, and for monitoring population cycles in areas where the vine mealybug is now entrenched. The traps have been the cornerstone of a statewide survey for this insect, and the pheromone is now commercially available from at least 3 companies in the US, and at least 2 companies in other countries.
Publications
- J. G. Millar, K. M. Daane, J. S. McElfresh, J. Moreira, R. Malakar-Kuenen, M. Guillen, and W. J. Bentley. 2002. Development and optimization of methods for using sex pheromone for monitoring vine mealybug in California vineyards. J. Economic Entomol. 95: 706-714
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Progress 01/01/01 to 12/31/01
Outputs
The sex pheromone of the vine mealybug Planococcus ficus has been identified as a single component, lavandulyl senecioate. Racemic lavandulyl senecioate was as attractive to male mealybugs as the insect-produced (S)-enantiomer, indicating that the unnatural enantiomer is not inhibitory. Lavandulol, which also was found in extracts from virgin females, antagonized attraction of males at higher doses. Rubber septum lures loaded with 10-1000 ug doses of the pheromone were equally attractive, and lures loaded with 25 ug of pheromone remained attractive for at least 12 wk under field conditions. Delta traps were more effective than double-sided sticky cards, and minimized captures of nontarget insects. Pheromone-baited traps had an effective range of at least 50 m. Comparison of visual sampling methods and sampling of males with pheromone-baited traps revealed that trap catches were significantly correlated with the results from visual sampling methods, and with economic
damage. Identification of the sex pheromones for grape, obscure, and longtailed mealybugs are underway, with laboratory colonies of all three species established, and pheromone collections being made to provide sufficient material for identification.
Impacts
Since its introduction into California less than 10 years ago, the vine mealybug has rapidly become one of the most important vineyard pests in table, wine and raisin grapes. Sex pheromone baited traps will provide a rapid method for sampling mealybug populations, leading to better control with fewer pesticide applications. The vine mealybug is also a pest worldwide, and the pheromone that we discovered is already being used in countries such as Israel and South Africa.
Publications
- Hinkens, D.M., J.S. McElfresh, and J.G. Millar. 2001. Identification and synthesis of the sex attractant pheromone of the vine mealybug, Planococcus ficus. Tetrahedron Letters 42:1619-1621.
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